Starting-switch interlocking device



Jan. 26 ,1926. v I v 1,570,616

- H. R. COFFMAN STARTING SWITCH INTERLOCKING DEVICE Filed March 5. 1925 1087262 F. Hoffman,

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Patented Jan. 26, 1925.

HURsHEL n. oo EMAN', or INDEPENDENCE, KANSAS.

STARTING-SWITCH. INTERLOCKING DEVICE.

- Application filed March a, 1925. Serial No. 12,889.

[0 all whom it may concern Be it known that I, HURsrrEL R. COFFMAN, a citizen of the United States, residing at Independence, in the county of Jackson and State of Missouri, have invented certain new and useful Improvements in Starting- Switch Interlocking Devices, of which the following is a specification. 7

My invention relates to an interlocking device for preventing the starting switch of a motor vehicle from being closed while the spark is advanced to such extent as to'be likely to cause back firing of the internal combustion engine, and my object is to provide a simple, inexpensive and efficient device of this character which can be readily installed without recourse to a skilled mechanic or special tools.

In order that the invention may be fully understood, reference will now be had to the accompanying drawing, in which:

Fig. 1 is a diagram of a portion of the starting switch and spark control mechanisms with my device connected thereto and in active position.

Fig. 2 is an enlarged side elevation of the starting switch with my interlocking device associated therewith and shown in active position in full lines and in inactive position in dotted lines.

Fig. 3 is a detail plan view of the interlocking device.

Fig. i is a longitudinal section on line IV-IV of Fig. 3. V

Fig. 5 is a cross section on line VV of Fig. 2.

Referring now in detail to the various parts, Adesignates the spark control lever, B the rod upon which the upper end of said lever A is fixedly mounted, C the starting switch, and D the pedal which is mounted on the plunger E of said starting switch 0. As the foregoing parts are of usual construction, further illustration or description thereof is deemed unnecessary.

Referring now more particularly to the 'parts constituting the present invention, 2

designates an interlocking member which is preferably formed into a loop 4 and has its ends connected by suitable means such as a bolt 5. One end of the loop 4 has an upwardly extending shoulder 6 reaching around to the opposite sides of said loop 4. The member 2 may be readily installed in position around the starting switch plunger E by removing the pedal D from the plunger cap H which projects over the shoulder 6. The pedal D is then replaced upon the plunger E. V

8 designates a retractile spring which is connected at one end to the bolt 5 and at its opposite end to any convenient part of the motor vehicle such as the frame G.

10 designates a rod or cable connected at one end to the forward end of the member 2 and at its opposite end to an arm 12 which is adjustably held upon the spark control rod B by suitable means such as a set screw 13.

When the parts are installed as shown and described, the member 2 is moved to inactive position by the cable 10 and the arm 12 when the spark control lever A is adjusted to the retarded position indicated by the arrow a,Fig. 1. The pedal D may now be de-' pressed for the purpose of starting the engine as the shoulder 6 has moved from beneath the cap H.

When the spark control lever A is advanced the cable 10 becomes slack and the interlocking member, 2 is moved to active position, Figs. 1 and 2, by the spring 8, the shoulder 6 comingto rest beneath the cap H. The interlocking member 2 remains in active position so that the pedal D can not be depressed for the purpose of closing the starting switch C until the spark control lever A is again restored to full, or substantially full, retarded position.

From the foregoing description it is apparent that I have provided means whereby all danger from back firing of the engine by starting the same through intermediacy of the starting switch while the spark is advanced, is effectually overcome; and while I have shown and described the preferred construction, combination and arrangement of parts, I reserve the right to make such changes as properly fall within the spirit and scope of the invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patcut, is:

1. A device of the character described consisting of a member adapted to hold the starting switch of a motor vehicle in open position, spring means for holding said member in active position when the spark controlling mechanism of the motor vehicle is advanced, and means connecting said memher to the spark controlling mechanism, so

that the latter When moved to retarded position may move the former to inactive position.

2. A device of the character described consisting of a member adapted to hold the starting switch of a motor vehicle in open position, means for holding said member in active position when the spark controlling mechanism of the motor vehicle is advanced, an arm connected to said spark controlling mechanism, and a cable connected to said arm and said member and whereby the latter is moved to inactive position when the spark controlling mechanism is adjusted to retarded position.

3. A device of the character described consisting of a member arranged to engage the pedal of a starting switch of a motor vehicle to hold said starting switch in open position, spring means for holding said member in active position and flexible means connecting said member to the spark controlling mechanism of the motor vehicle so that said mechanism may move said member to inactive position.

In a device of the character described, a loop-shaped member adapted to loosely embrace a starting switch plunger and having upwardly projecting shoulders for engaging under a cap on said plunger.

In testimony whereof I afiix my signature.

HURSHEL R. COFFMAN. 

